By reducing the off-delay interval to 30 seconds, a building owner can see energy savings of more than 75%.

Occupancy-controlled lighting has become a very common feature in homes and apartments and can offer significant energy savings, but the amount of potential savings is directly related to the off-delay setting—the time that the light stays on after occupancy is no longer detected. Building owners can save money by taking the first step of installing occupancy controls, even with an off-delay of 30 minutes, the maximum setting suggested by the ASHRAE 90.1-2010 lighting standard. For many building spaces, however, significantly greater energy savings can be gained by further reducing the lighting off-delay setting. Figure 1 illustrates how, under identical occupancy conditions, the amount of time that the lights remain on in a vacant space can vary greatly depending on the off-delay setting, especially when people enter and leave the space frequently.